<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script>
    let arr= [1,3,3,3,2,2,5,6,7,84,4,3,3,3]
    for (let i=0;i<arr.length;i++){
        for (let j=i+1;j<arr.length;j++){
            if(arr[i]===arr[j]){
                arr.splice(j,1)
                j--;
            }
        }
    }
    console.log(arr.toString())
</script>
</html>
